Valves for controlling the flow of fluids such as water and gas in conduits often are subjected to tremendous pressures. For example, if a single wedge valve is used, the valve itself is subjected to both lift and sideways pressure which can create leaks or cause the valve to bind. Such a valve, in a high-pressure environment within a conduit, requires tremendous power to move between open and closed positions.
Known types of valves such as gate valves and butterfly valves are subjected to significant drag forces during operation, particularly in high-pressure environments.
The use of balanced valves, to reduce the drag that otherwise exist on a valve in a conduit is known. The concept is that, by splitting the flow of fluid as it approaches a valve the power required to activate the valve is significantly reduced as is the drag on the valve.
Examples of balanced valves for a wide variety of applications are described and illustrated in U.S. Pat. No. 38,746 of Horell, issued Jun. 8, 1863; U.S. Pat. No. 285,955 of Barry, issued Oct. 2, 1883; U.S. Pat. No. 1,507,280 of Gomand, issued Sep. 2, 1924; U.S. Pat. No. 1,649,953 of Ernst, issue Nov. 22, 1927; U.S. Pat. No. 1,744,221 of Gomand, issued Jan. 21, 1930; U.S. Pat. No. 2,130,614 to Collins et al., issued Sep. 20, 1938; U.S. Pat. No. 2,669,417 to Ray, issued Feb. 16, 1954; U.S. Pat. No. 2,750,145 of Thornros, issued Jun. 12, 1956; U.S. Pat. No. 4,573,492 of Tadokoro, issued Mar. 4, 1986 and U.S. Pat. No. 6,030,174 of Maier et al., issued Feb. 29, 2000. These patents teach various types of valve constructions where fluid flow is equally diverted from a single conduit to pairs of conduits, the valves controlling the flow of fluid through these two conduits.
It is an object of the present invention to provide a novel construction of balanced valve which will have a variety of applications and provide effective sealing and operation at high pressures.